Here we are, the last test session ended up yesterday, after yet another 4h of non-stop play. Only a dozen of minor problems were found, and I even had the time to correct every single one of them today. For the moment, the game is officially bug-free.
Of course, we all know a game can't be bug-free, especially when we're only testing it during our spare time, without any professional means of some sort. But we believe we reached a fairly mature stage. To conclude, the beta version is nearly finished.
For the moment, we're working on the last map, tweaking things a bit, adding details and reducing the overall difficulty and complexity (to understand what one must do). There's still some changes to overtake, but with this last map, we're already flirting with the limits of the engine, we must be careful.
So, I believe we can unveil the real release date, because we think that we'll have plenty of time to polish things up until this date. When we published our first news, we said "somewhere around the end of september or the beginning of october". It appears it will more likely be on the beginning of october.
Now it's rather official, we plan to release the whole thing on the first birthday of the Orange Box. October 10th.